Hmmm... interesting. I'm lacking and elocker and getting a very similar vibration, but it starts at 35, and like a light switch too. After replacing all 3 U Joints, didn't happen beforehand or after taking it out the first time. Is it an oscillating sound, and feels kinda like someone driving next to you with bumping subs?
I assumed it was because I installed the slip yoke 180*, but I flipped it around and it was profoundly worse and constant, along with getting worse at 35+, so I chalked it up to some of the metal removed from the cardan yokes after galling the metal trying to fit the new bearings (didn't watch Tim's video
)
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Y2K Highlander
Millennium Silver 3.4L auto @ 320k and climbing
Toytecs + 5100s / 7.5 wrap + OME spacers + Tokicos / JBA UCAs / Anonymous Fab. LBJs / Total Chaos Gussets / EimKeith PCK + LCAR / Extended Bump Stops; Brake Lines; Rear Diff Breather / True North Fab. Hybrid Bumper / CBI Hybrid Bumper + Tire Carrier / 4xInnovations Hybrid Sliders / Opt Offroad Trailing Arms / Lil Skip Gas Skid / BudBuilt Front Skid / ARB Rear Locker